2023-03-25 16:03:06 +01:00

68 lines
2.3 KiB
Rust

const FLASH_BASE: u32 = 0x0800_0000;
pub(crate) const SMALL_SECTOR_SIZE: u32 = 32 * 1024;
pub(crate) const MEDIUM_SECTOR_SIZE: u32 = 128 * 1024;
pub(crate) const LARGE_SECTOR_SIZE: u32 = 256 * 1024;
#[derive(Debug, PartialEq)]
pub struct FlashSector {
pub index: u8,
pub start: u32,
pub size: u32,
}
pub fn get_sector(address: u32) -> FlashSector {
// First 4 sectors are 32KB, then one 128KB, and rest are 256KB
let offset = address - FLASH_BASE;
match offset / LARGE_SECTOR_SIZE {
0 => {
if offset < 4 * SMALL_SECTOR_SIZE {
let small_sector_index = offset / SMALL_SECTOR_SIZE;
FlashSector {
index: small_sector_index as u8,
start: FLASH_BASE + small_sector_index * SMALL_SECTOR_SIZE,
size: SMALL_SECTOR_SIZE,
}
} else {
FlashSector {
index: 4,
start: FLASH_BASE + 4 * SMALL_SECTOR_SIZE,
size: MEDIUM_SECTOR_SIZE,
}
}
}
i => {
let large_sector_index = i - 1;
FlashSector {
index: (5 + large_sector_index) as u8,
start: FLASH_BASE + 4 * SMALL_SECTOR_SIZE + MEDIUM_SECTOR_SIZE + large_sector_index * LARGE_SECTOR_SIZE,
size: LARGE_SECTOR_SIZE,
}
}
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn can_get_sector() {
let assert_sector = |index: u8, start: u32, size: u32, addr: u32| {
assert_eq!(FlashSector { index, start, size }, get_sector(addr))
};
assert_sector(0, 0x0800_0000, SMALL_SECTOR_SIZE, 0x0800_0000);
assert_sector(0, 0x0800_0000, SMALL_SECTOR_SIZE, 0x0800_7FFF);
assert_sector(3, 0x0801_8000, SMALL_SECTOR_SIZE, 0x0801_8000);
assert_sector(3, 0x0801_8000, SMALL_SECTOR_SIZE, 0x0801_FFFF);
assert_sector(4, 0x0802_0000, MEDIUM_SECTOR_SIZE, 0x0802_0000);
assert_sector(4, 0x0802_0000, MEDIUM_SECTOR_SIZE, 0x0803_FFFF);
assert_sector(5, 0x0804_0000, LARGE_SECTOR_SIZE, 0x0804_0000);
assert_sector(5, 0x0804_0000, LARGE_SECTOR_SIZE, 0x0807_FFFF);
assert_sector(7, 0x080C_0000, LARGE_SECTOR_SIZE, 0x080C_0000);
assert_sector(7, 0x080C_0000, LARGE_SECTOR_SIZE, 0x080F_FFFF);
}
}